Abrasive wheel assembly



April 17,1956 (5. o. LEGGETT ABRASIVE WHEEL ASSEMBLY Original Filed Sept. 8. 1953 INVLNTOR.

- 1 61g, 0 Ze v rf/ A/BRASIVE WHEEL ASSEMBLY O. Leggeit Van Nuys, Calif lssignor to erlt Productalnc Culver City, Calif.-

No. 2,678,523, dated May is, 1954, Serial No.

OIIIIIIII 1 378,716, September 8, 1953. Application for reissue September 29, 1955, Serial No. 537,614

10 Claims. (Cl. 51193.5)

in heavy brackets appears in the This invention relates to 'an abrasive wheel assembly, the present application pertaining to'an improvement in certain particulars of the flexible abrasive wheel of my co-pending United States application for patent,'Serial United States Patent -No.. 76,316, filedMarchlS, 1952, which issued Septem- I her 5, 1953, as Patent No. 2,651,894. The present invention relates to a simplification of the structure disclosed in my said co-pending application,

' and particularly in regard to alternating non-abrasive flaps with abrasive ones and to applying to the inner.

part of the annular pack of abrasive flaps an improved "non-metallic reinforcing means, thus making itpossible to use a si plified clamping means to secure the assembled pack f flaps to the means for mechanically rotating them during the abrading operation.

Aceordinly, one feature, of the'invention relates to provisi n, as a new article of manufacture, of an annular'pack of flaps, some provided with abrasive surface'portions and others with non-abrasive faces only,

' and particularly well adapted to be clamped to a meprovide, in an abrasive wheel, an assembly of abrasive and non-abrasive flaps which can be manufactured at a lower .costfand which can be more easily assembled; to provide for a better polishing operation; to provide a clampingmeans that can be relied upon to grip the assembled annular pack of abrasive flaps in a more dependable, secure manner for mechanical rotation at a high speed; and 'to improve various mechanical details of the structure with a view to rendering the device more durable "and making it more dependable in its operation.

An additional; important object is to provide in an abrasive wheel, a combination of abrasive flaps with less costly non-abrasive ones, the non-abrasive flaps being terleaved with the abrasive ones in such a manner that e latter do not contact with and wear out each other during the rotation of the wheel, with the result that the usablelife of the whole assembly is considerably lengthened.-

Other objects, advantages and features of invention will hereinafter appear.

Referring to the accompanying drawing which illustrates a preferred, reduced to practice embodiment of the invention,

Fig. 1 is a perspective view showing, per se, the replacement unit of the abrasive wheel which constitutes the new article of manufacture provided by the invention. Some of the flaps in the part of the wheel nearest to the observer are shown diverging from each other more than normally so as to illustrate to what the means for mounting said annular packs.

the remainder of. the wheel the flaps thereof are shown in their normal position with parts of the wheel delineated in phantom lines to simplify illustration.

Fig. 2 is a vertical mid-section of the complete wheel assembly. c

Fig. 3 is a perspective 'view of the complete wheel assembly showing the parts in an axially spaced relation to each other, the replacement element per se being delineated, partlyby full and partly by phantom lines.

Referring in detail to the drawing, and particularly to Fig. 3, where the parts are shown in an axially extended relation to each other, the metallic arbor, generally designated 5, comprises a cylindrical body portion 6 which has a screwthreaded portion 7 occupying the greater part of its length, a hexagonal, peripheral flange 8 being'shown at theinner end of said screwthreaded portion. Said arbor has a shank 9 for connection with a driving means 10, ordinarily a chuck.

Said arbor 5 is located concentrically of an annular pack 12 of rectangular flaps which comprises abrasive: flaps l4 alternating with non-abrasive flaps 15, said arbor carrying a pair of twin'discs 17 which form a part of A fabric strip 19 is adhered to the inner ends of the annularly assembled flaps.

An annular core member 20 desirably made of fiberboard or of a stiff strip of pasteboard has its exterior surface of said fabric strip 19, and as an additional means for maintaining said pack in annular form a pair of annular canvas strips 22 are adhered, one to each side of the inner portion of said pack, the inner edge portions, of said strips overlying the ends of the aforesaid member. 20 and being adhered to said ends. Y i

Each of the aforesaid twin discs 17 is concave-convex, its convex side being directed toward the midwidth of the structure of which it forms a part. These discs are centrally apertured 'so as to fit closely but slidably around the screwthreaded portion 7 of the aforesaid arb r, and each disc is shown provided around its central aperture with an annular flange 23 whichprojects from its convex side. The peripheral portion of each ofsaid discs is provided internally Wllh'tll'l annular flange or circular shoulder 24, and radially therebeyond with an annular flange portion 25, each of flanges 24 internally abutting the aforesaid annular member 20 and each said flange portion 25 abutting the outer face of the aforesaid canvas strip at its side of the device. completes the mounting means for the pack of flaps,

said nut preferably having its inner face recessed as indicated at 29, so that only its peripheral portion abuts the disc against which it is clamped.

The following method may be used to form'the flaps:

A roll of abrasive cloth coated with the abrasive on one face only, one inch wide is mounted on a spindle, said spindle being carried by a vertical panel. Subjacent to this roll on a parallel spindle a roll of uncoated paper is mounted on the same panel. These strips carried by these two rolls are horizontally directed in a contacting relation to each other and are advanced by means of a pair-of mechanically driven feed rollers between which they pass. These advancing contacting strips are intermittently cut off by a suitable mechanically operated knife, each cut off pair of flaps dropping down into a receiver and allowed to accumulate in said receiver until they form a long, vertical pack, for exam- 7 ple, three feet in length. The receiver within which this pack is formed has an open side portion affording access Re. 24,143 a V A clamping nut 27' coated face uppermost.

- faces.

5. As an article of manufacture, an annular pack of' done and the glue has become dry the pack iscut' into lengths each of which equals the length of the pack.

equal to the internal diameter of said ring 20. Next, one of the annularv canvas strips 22 has a coating of fresh adhesive applied to one of its faces and said strip is pushed down around said core member with its freshly Thereupon the annular pack is strip is coated with a maa,

'is placed" upon a horizontal surface in an upstanding position the diameter of this member being substantially placed around the core member and its lower side placed 1 against said freshly coated adhesive face, and finally the other'canvas strip 22 is likewise coated with adhesive on one face and is passed downwardly over the upper end of the core member and has its freshly coated face pressed against the top surface of the pack. After this pair of strips 22 has adhered to the pack the new article of manufacture formed by the pack is complete.

'* The mounting of the aforesaid pack upon and between the discs 25 provided therefor will be readily understood from what has already been said about the construction of the metallicpart of the device, as shown in a spaced apart manner in Fig. 3 and assembled in Fig. 2.

' The non-abrasive flaps are preferably made of a'low priced wrapping paper. facture is considerably reduced andalso the wearing life .of the wheel is increased about twenty-five per cent.

I claim:

' 1.. As an article, of manufacture, an annular pack of juxtaposed flaps, and means adhered to said flaps maintaining them circularly disposed-around a central, circular space, alternate flaps of said packeach having a facecoated with an abrasive substance, and the inter vening flaps 'each havingsmooth faces;

2. The subject matter of claim 1 and said flaps having dinner end edges and said means for holding said' fiaps in pack formation comprising a non-metallic ring occupying said central space-and adhered to said end edges of the fiapsof the pack, whcrethey border said space, and

an annular fabric ring of sheet material at each side of the pack adhered to' aside ,of the pack circumjacent to said circular-space.

3. The subject matter of claim 1 and said flaps havinginner end edges and said-means for holding said flaps in pack formation comprising a non metallic ring occupying said central space and adhered to said end edges of the flaps ofv the pack where they border said space, and an 'annular fabric ring of sheet material at each side of the pack adhered both to an end of said ring and to a side of the pack circumjacent to said circular space.

4. As an article'of manufacture, an annular pack of juxtaposed flaps having inner end edges, and a pair of annular fabric strips of sheet material one of said strips havingone of its faces'adhered to one face of said pack circumiacent to the space which the pack surrounds and the other of said annular strips having one of. its faces adhered to the opposite face of the pack circumjacent to the space which pack surrounds,'alternate flaps of sa'idlpack each having a face coated with an abrasive substance and the intervening flaps each having smooth juxtaposed flaps, and means adhered to said flaps maintaining them circularly disposed around a central, circu' -lar.space, said pack comprising a series of circumferen- By their use the cost of manu dolly rectangular leaves apan each; other in oblong:

row, holding said leaves in tight parallel 'proxir'nity'to each other with one of their end edges exposed, applying a coating of adhesive to the exposed edges of said leaves,

applying an elongated fabri'c'st'rip on top said adhesive, drying said adhesive, said adhesive binding. said leaves to said fabric strip to form an elongated resilient strip I of leaves capable of being handled without separation of said leaves from said strip, cutting said strip into a plurality of length: corresponding to the inner circumference of the abrasive grinding wheels being formed, bending each of said lengths into a complete circle, and adhering the opposite. side of each of said fabric strips to a substantially rigid circular core.

7. The method'of forming an abrasive grinding wheel comprising assembling a plurality of separate substantially rectangular leaves adjacent each other in a long row, holdingsaid leaves in tight parallel proximity to each other with one of their end edges exposed, applying a coating of adhesive tothe exposed edges of said leaves, applying an elongated fabric strip on top of said adhesive, drying said adhesive, said adhesive binding said leaves together .to formnn elongated resilient strip of leaves capable of being handled without separation of said leaves from said strip bending said strip of leaves into a complete circle, and adhering the opposite side of said fabric strip to a substantially rigid circular core.

8. The method of forming an abrasive grinding wheel comprising assembling a plurality of separate leaves adjacent each other in a long row, holding said leaves-gin tight proximity to each other with one of their edges exposed, applying a coating of adhesive to the exposed edges of said leaves, applying a flexible strip on top of ing said leaves together to form an elongated resilient. strip of leaves capable of being handled without separation" of said leaves from said strip, bending said strip of leaves into a complete circle, and adhering the opposite side of saidnon rigid strip to a circular core.

9. The method of forming an abrasive grinding wheel 7 comprising assembling a plurality of separate leaves ad- 'iacent each other, at least some of said leaves carrying abrasive coating material, a portion of each of said leaves being exposed, attaching a flexible strip to the exposed portions of a substantial number of said leaves simultaneously with adhesive, drying said adhesive, said adhesive binding said leav'es'together to form an elongated resillent strip of leaves capable of being handled without separation of said leaves from said strip, bending said strip of leaves into a complete circle; and adhering sold strip of leaves to a circular member.

10. The method of forming an abrasive grinding wheel comprising assembling a plurality of separate leaves adiacent each other in a long row, at least some of said leaves carrying an abrasive coating material, holding said leaves in tight proximity to each other with one of their edges exposed, applying a coating of adhesive to the exposed edges of a substantial number of said leaves simultaneously,'applying a flexible strip on top of said adhesive, drying .roid adhesive, said adhesivebinding said leaves together to form an elongated resilient strip of leaves capable of being handled without separation-of'mid into a complete circle to form said abrasive'wheel.

References Cited-in the file of this patent or the original patent UNITED STATES PATENTS 101,058 Siiwerkrop Mar. 22, 1870 244,699 Ware July 19, 1881 372,041 Pfleghar .1. Oct. 21, 1887 410,749- Colburn Sept. 10, 1889 449,239 Webster Mar. 31, 1891 (Other references on following page) I NITED STATES PATENTS Cummins June 30, 1891 Condon e181 Dec. 21,1897 ,Graham May 10, I898 Cook Oct. 11, 1898 Williams May 1, 1900 Piper Sept. 19, 1911 Courtney Dec. 12, 1911 Brinkman 'Apr. 23, 1912 6 Johnston Feb. 14, 1933 Hillix Sept. 24,1935 Feucrstcin Oct. 22. 1935 Levoy Nov. 15. 1938 Davis July 4. 1939 Nordgren ct ul July 15, I947 Crumbling et a1. June 29, 1948 Bahr May 2, 1950 Harman Oct. 3, 1950 

